Some movies, like the one on
the left, play automatically. Press the space bar to stop and start
these movies, or use the control bar below the movie.

Virtual reality
(VR) movies, like the one on the right, do not have a control bar --
instead you rotate or otherwise change a block by clicking and dragging the cursor
(left and right, or up and down) inside the movie. Small, labeled arrows above
each movie
indicate how you can change the block.